Effective Drugs Not Limited To Brand Names

March 02, 1986|By G. Timothy Johnson, M.D.

Dear readers: One of the more interesting questions being debated in medical and public press is whether generic drugs are as ``effective`` as brand-name drugs. This issue becomes more pertinent as additional generic drugs are introduced into the marketplace.

For example, generic forms of Inderal and Valium recently have been approved by the U.S. Food and Drug Administration. The increasing numbers of generic drugs being introduced is a result, at least in part, of a new law in effect since September 1984 that makes it much easier for the FDA to approve generic products.

The Jan. 3, 1986, issue of the Medical Letter contains a discussion of the effectiveness of generic drugs vs. brand-name products. It points out that many generic drugs actually are made by brand-name firms and vice versa. That is why some states now require the manufacturer of the drug to be identified on product labels.

The Medical Letter also points out that historically, only a few serious differences have been reported between brand-name originals and generics (in terms of their ``bioavailability``--the degree to which the drug can be used in the body). In fact, the problems were not always associated with the generic products.

For example, some generic digoxin products were found not to be absorbed as well as the original formulation. But Dilantin Kapseals, on the other hand, were not as reliably absorbed as various generic formulations of Phenytoin.

Few other well-documented, clinically significant discrepancies in bioavailability between brand-name originals and FDA approved generics have been reported, according to the Medical Letter.

``The newly approved generic drug products now being marketed will probably prove to be as reliable as brand-name drugs. Whether using brand name products or generics, the possibility of product failure should always be kept in mind.``

Dear Dr. Johnson: What is the difference between a flexible and rigid sigmoidoscope?

The difference is the one literally suggested by the two terms. A rigid sigmoidoscope is the one that patients may know as the ``silver bullet``

because it is a rigid tube, silver in color, that cannot bend. As such, there is a limit as to how far it can be inserted into the lower end of the large intestine through the anus.

The flexible sigmoidoscope can be bent and turned around corners. It can be inserted approximately three times as far as the rigid sigmoidoscope.

The flexible construction is the same principal used in the much longer colonoscope, which can be inserted through the entire length of the large intestine to the point where it joins with the end of the small intestine.

The flexible sigmoidoscope has the advantage of a greater distance of insertion and usually of more patient tolerance and comfort.